# Problem to create NDVI map (Parrot Sequoia+)

**URL:** <https://community.pix4d.com/t/problem-to-create-ndvi-map-parrot-sequoia/15003>\
**Category:** PIX4Dmapper\
**Created:** [October 15, 2020, 10:52pm UTC](https://community.pix4d.com/t/problem-to-create-ndvi-map-parrot-sequoia/15003 "2020-10-15T22:52:15Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![b.candido](https://sea2.discourse-cdn.com/pix4d/user_avatar/community.pix4d.com/b.candido/32/2813_2.png) [@b.candido](https://community.pix4d.com/u/b.candido)\
**Post date:** [October 15, 2020, 10:52pm UTC](https://community.pix4d.com/t/problem-to-create-ndvi-map-parrot-sequoia/15003/1 "2020-10-15T22:52:15Z")

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Dear,

I am trying to generate a reflectance map and after steps 1 and 2 it shows the error message:

“generate reflectance map (green) failed!”

What can I do to solve it?

Kind regards,  
Bernardo

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**Author:** ![momtanu.chakraborty](https://sea2.discourse-cdn.com/pix4d/user_avatar/community.pix4d.com/momtanu.chakraborty/32/269_2.png) [@momtanu.chakraborty](https://community.pix4d.com/u/momtanu.chakraborty)\
**Post date:** [October 16, 2020, 1:41am UTC](https://community.pix4d.com/t/problem-to-create-ndvi-map-parrot-sequoia/15003/2 "2020-10-16T01:41:34Z")

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Bernardo, This might be related to read/write permission. I see you are using the dropbox folder. Can you try to use a local directory and let me know if that works?